‘A little. We have evidence of a splash, a little upstream from where the body was found, witnessed by a number of people at around two a.m., which is three hours before he was found. The location of that splash would be a possible site for a body to be thrown out of the boot of a car. We have a number of active leads we are pursuing—’

‘Right, so not actually much progress then,’ Delahaye said, grinning conspiratorially at Rainy. ‘Let’s turn him over, shall we?’ He called over a technician, who helped turn the body face down. The cyanosed impression of a diamond grid on his back, shoulders, buttocks and thighs was extremely clear. Whatever it was he had been crushed against had broken thousands of capillaries across his body.

‘There is one idea I had, which you will probably consider is stupid,’ Rainy said. ‘This could have been a sex game gone wrong.’

‘Very wrong, I would have thought,’ Gillard said.

‘Och, you’d be gobsmacked what we saw in A&E. You can never say anything is too extreme for people to have a go at. The items they will insert, the inventiveness. You wouldnae believe it.’

‘Yes,’ said Delahaye with unusual enthusiasm. ‘When I was a medical student, I was present for a champagne celebration. Including the removal in theatre of the empty Krug bottle from a middle-aged woman.’

‘Aye, I’ve done a couple of those,’ Rainy said dismissively. ‘You have to drill through the bottle to break the airlock—’

‘Then squirt some baby oil into the vaginal canal so you can ease it out,’ Delahaye said.

‘No, this is much more extreme,’ Rainy said, shaking her head.

Gillard, open-mouthed, looked from one to the other. ‘You’re not kidding.’

‘What I’m thinking,’ Rainy said, ‘is that partial asphyxiation is a known method of enhancing the power of an orgasm. So the victim dresses up in his own mesh playsuit—’

‘—and gets crushed to death,’ Gillard said. ‘What fun! And then gets tossed into the river by someone else who, incidentally, pinches his playsuit.’

‘Aye, sir,’ Rainy said. ‘I said it was stupid.’

Claire Mulholland knew that Baz had enjoyed an interesting day from the texts he had sent her. When she arrived to pick him up, shortly after six, he was full of the story of the large reptile house that he and his colleague were preparing. ‘That is going to be some serious zoo,’ he told her, as he sat himself down in the passenger seat of her car, his dusty overalls and a large plastic carrier bag between his knees. ‘But it’s just for the sheikh’s own pleasure.’

‘What did you see?’